Multi-domain vertical alignment (MVA) is a known mode among display modes in liquid crystal display devices. In MVA mode liquid crystal display devices, there is used a liquid crystal having negative dielectric constant anisotropy, sealed between a pair of substrates, a vertical alignment layer that causes liquid crystal molecules to be aligned substantially orthogonally with respect to the surface of the substrates, and an alignment regulating structure that regulates the alignment direction of the liquid crystal molecules. Examples of the alignment regulating structure include, for instance, linear protrusions comprising a dielectric, and electrode cutouts (slits). A wider viewing angle can be obtained in such MVA mode liquid crystal display devices by providing, in one pixel, a plurality of regions (domains) in which the liquid crystal molecules have mutually dissimilar alignment directions, by way of such an alignment regulating structure.
However, in MVA mode liquid crystal display devices, a drop in light transmittance during white display tends to be generated at the boundaries between domains, for instance at regions where linear protrusions or slits are provided in the pixels. The liquid crystal response time drops in a case where the arrangement spacing between alignment regulating structures is widened in order to suppress the above occurrence. Therefore, alignment films may be subjected to aligning treatments for imparting initial alignment to the liquid crystal, in terms of conferring fast response to the liquid crystal while curtailing a drop in light transmittance during white display. MVA mode liquid crystal display devices, however, are provided with an alignment regulating structure, and hence an aligning treatment by rubbing is ordinarily not carried out.
In this context, known effective technologies for achieving MVA mode liquid crystal display devices include polymer-sustained alignment (PSA). PSA is a method wherein a polymerizable component such as a monomer or oligomer is mixed into the liquid crystal, and the polymerizable component is polymerized in a state where the liquid crystal molecules are obliquely aligned through application of a voltage to the liquid crystal, as a result of which a polymer having a memory of the direction in which the liquid crystal falls becomes provided on a substrate (for instance, Patent document 1).
In organic EL displays, thus far, canister-sealed structures have been ordinarily employed wherein a drying agent is affixed to a carved glass, and the outer side of the outer periphery of an organic EL element is sealed, in a frame-like manner, by way of a sealing resin, in order to prevent deterioration of the organic EL element caused by external oxygen or moisture. Such a canister-sealed structure, however, makes it difficult to adopt top-emission structure in which light is extracted from the top face of the panel (increase in aperture ratio), and to realize thin-profile panels. Therefore, sealing structures that employ flat substrates (hereafter, flat sealing structures) have been developed in recent years. Specifically, technologies have been developed in which an organic EL element is sealed by affixing a flat substrate onto the organic EL element, by way of an adhesive that comprises a photosensitive resin.
In conventional display device substrates, in particular in TFT (thin film transistor) array substrates (hereafter also referred to as TFT substrates), a photosensitive resin film having a planarizing effect is formed, as an interlayer insulating film, from the viewpoint of suppressing disconnection in wiring. As such interlayer insulating films there has been disclosed, for instance, a radiation-sensitive resin composition that comprises a radiation-sensitive acid-generating compound and a resin that is soluble in an alkaline aqueous solution and that contains, in one molecular chain, a carboxyl group or an anhydride and an epoxy group (for instance, Patent document 2).
Patent document 1: JP 2003-149647 A
Patent document 2: JP 5-165214 A
In conventional PSA mode liquid crystal display devices (liquid crystal display devices manufactured using PSA technologies), and in organic EL displays having flat-plate substrates, however, gas and/or bubbles may occur in a pixel region after a step of polymerizing a monomer dispersed at the pixel region through UV irradiation, or after a step of curing an adhesive comprising a photosensitive resin through UV irradiation, whereby a defective device could have been produced. FIG. 35 is a plan-view schematic diagram illustrating a conventional PSA mode liquid crystal display panel. In an impact test of a PSA mode liquid crystal display panel after an UV irradiation step, bubbles 139 could be jetted into a cell in a pixel region P, as illustrated in FIG. 35, on account of the impact. In the impact test, a pachinko ball was dropped onto a panel from a height of 30 cm, at high temperature (80° C.).